1. What is Additive Manufacturing More common name: 3D-printing Layer-based technology Designs are created or scanned using computer software, usually CAD Printers import dataset then create the object from many layers of equal thickness Construction Automation First construction robot: WASCOR (Waseda Construction Robot) from Japan Using push-up method SMART (Shimizu Manufacturing by Advanced Robotics Technology) from Japan ABCS (the Automated Building Construction System) from Japn TAMIR (Technion Autonomous Multi-purpose Interior Robots) from Israel Contour Crafting Developed by Professor Behrokh Khoshnevis A Mega-scale fabrication technology The purpose of the research is to solve some major problems of conventional construction: Create a more accurate building Reduce the cost and construction building Reduce waste generated and injuries of workers Contour Crafting System: Consists of an extrusion system that conveys a mortar mixture Piston connected to a screw that rotates at a demanded speed The scale of the construction is determined by the scale of the system Trowels are attached to the side of the nozzle to smoothen the surface Full Scale Concrete Wall Construction using Contour Crafting Conventional concrete wall construction needs complicate formwork which does not work for CC constructed walls New formwork needs to be designed and it should withstand lateral pressure The new-designed formwork becomes part of the structure permanently Best formwork material mixture was found The structure of the formwork is different Mix Design of a High-performance Concrete Experiments were carried out to find the ideal mix design of the high-performance concrete The optimum mix was found to have a 3:2 sand-binder ratio with the latter consisting 70% cement, 20% fly ash and 10% silica fume plus 1.2 kilograms per cubic meter of 12/0.18 length/diameter polypropylene fiber Also a water-binder ratio of 0.26 together with a superplasticiser and retarder with dosages of 1 and 0.5% by weight of binder Application of this technology: House in Amsterdam Used a giant printer “Kamermaker” Rooms are printed separately and then put together The house were made of bio-plastic 80% made from plant oil The house itself is recyclable No need for bringing bricks and concrete Application of this technology: Houses in Shanghai, China 10 houses were built using CC in less than 24 hours Used concrete from construction wastes Saves 30%-60% on building materials, 50%-70% on time and 50%- 80% on number of workers The cost was reduced to half Low cost houses benefit lower-class people in developing countries like China Application of this technology: In Space NASA and ESA are interested in expanding human territory in space by settling bases on the Moon and Mars Cost around $2 million to send an ordinary brick to the Moon Safety issues when using workers to construct shelters Additive Manufactured constructions are ideal for shelters in space Due to the extreme environment, current technologies need a lot improvement Drawbacks and Concerns Large scale systems are hard to transport and very expensive to maintain Choices of building materials are limited to certain kinds of concrete mixtures Unlike conventional constructions, amendments cannot be made during the process. So all the sequences need to be planned in advance Imagine: Future of this technology People purchase designs online and send them to the construction team. The team will bring the printer to site and the house will be built in less than 24 hours with cables and pipes. Low cost houses for lower-class people. Free shelters for underdeveloped countries. Human expand their territory into space. No astronauts need to risk their life